target/linux/generic/backport-6.1/611-v6.3-net-add-helper-eth_addr_add.patch

   1 From 7390609b0121a1b982c5ecdfcd72dc328e5784ee Mon Sep 17 00:00:00 2001
   2 From: Michael Walle <michael@walle.cc>
   3 Date: Mon, 6 Feb 2023 13:43:42 +0000
   4 Subject: [PATCH] net: add helper eth_addr_add()
   5
   6 Add a helper to add an offset to a ethernet address. This comes in handy
   7 if you have a base ethernet address for multiple interfaces.
   8
   9 Signed-off-by: Michael Walle <michael@walle.cc>
  10 Reviewed-by: Andrew Lunn <andrew@lunn.ch>
  11 Acked-by: Jakub Kicinski <kuba@kernel.org>
  12 Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
  13 Link: https://lore.kernel.org/r/20230206134356.839737-9-srinivas.kandagatla@linaro.org
  14 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  15 ---
  16  include/linux/etherdevice.h | 14 ++++++++++++++
  17  1 file changed, 14 insertions(+)
  18
  19 --- a/include/linux/etherdevice.h
  20 +++ b/include/linux/etherdevice.h
  21 @@ -508,6 +508,20 @@ static inline void eth_addr_inc(u8 *addr
  22  }
  23
  24  /**
  25 + * eth_addr_add() - Add (or subtract) an offset to/from the given MAC address.
  26 + *
  27 + * @offset: Offset to add.
  28 + * @addr: Pointer to a six-byte array containing Ethernet address to increment.
  29 + */
  30 +static inline void eth_addr_add(u8 *addr, long offset)
  31 +{
  32 +       u64 u = ether_addr_to_u64(addr);
  33 +
  34 +       u += offset;
  35 +       u64_to_ether_addr(u, addr);
  36 +}
  37 +
  38 +/**
  39   * is_etherdev_addr - Tell if given Ethernet address belongs to the device.
  40   * @dev: Pointer to a device structure
  41   * @addr: Pointer to a six-byte array containing the Ethernet address